Circularly Polarized Stack-Patch Microstrip Array Antenna for Mobile Satellite Communications

Nowadays, the knowledge of science and technology, especially in the field of mobile satellite communication is developing hugely and rapidly. It is included the development of the ground station antenna as transceiver signal to make a good conducted communication between the satellite and terminal station at the earth. Moreover, as geostationary satellites are remotely located (about 36,000 km) from the earth, the incoming wave is very weak. Consequently, it is required that the antenna for mobile satellite communications has a high gain in the case multimedia communications performing large-capacity data communication is aimed. In order to obtain a good performance antenna to clarify suitably result on frequency characteristic, return loss, and radiation pattern, and also to obtain a simple configuration such as small, light and low profile, a left-handed circularly polarized stack-patch microstrip array antenna is proposed [1]-[2]. The antenna configuration instead of receiver and transmitter which is combined becomes array antenna at frequency target 2.48 GHz and at 2.63 GHz, respectively. The antenna was calculated by the Method of Moments using probefed pentagonal array antenna as radiating patch and triangular array antenna as parasitic patch with dielectric relative permittivity 2.17 and loss tangent 0.0009.[3]-[6] In this paper, it discuss about the performances of that antenna at El=48° with calculation results. The calculated results both receiver and transmitter antenna at El=48° are satisfied about 5 dBic gain, and the 3-dB axial ratio beamwidth. The whole azimuth range about more of 120° for each beam coverage in the conical-cut direction also satisfy for mobile satellite applications, especially for Japan areas. Keywords—circularly polarized; stack-patch; receiver and transmitter; array antenna